H ebsworth



Jan. 24, 1956 R. H. EBswoRTH POWER TRANSMISSION 3 Sheets-Sheet l Filed March 7, 1950 Jan. 24, 1956 R. H. EBsWoRTH POWER TRANSMISSION 3 Sheets-Sheet 2 Filed March 7, 1950 m SQ @my w@ SMQ ew NS www INVENTOR /P/Cf/A/ea A( issn/0km'.

\ ATTORNEYS.

Jan. 24, 1956 R. H. i-:BswoRTH POWER TRANSMISSION 3 Sheets-Sheet 3 Filed March 7. 1950 INVENTOR R/cf/Aea asn/0km',

ATTORNEYS tw QN N RN; N

United States Patent O 2,731,848 POWER TRANSMISSIN Richard H. Ebsworth, Laguna Beach, Calif. Application March 7, 1950, Serial No. 148,227 23 Claims. (Cl. 743-472) nish an innite range and driven shafts.

The invention comprises front and rear planetary gearsets, front and rear clutches spring actuated and hydraulically disengaged and front and increase in the torque transmitted.

It is a further feature of this invention that gear members in the front planetary gearset are utilized to provide the resistance pump; said members being iitted with a casing and performing their pumping function without the use of any cooperating gears external to the said casing.

Other advantages, objects and features of this invenpressures for their operation; the use of only one pressure pump with simplified conduits for operating the controls; and provision for pressure from the pressure pump in top gear thus reducing drag on the drive shaft.

These and other features, objects and advantages will be apparent from the annexed specification in which:

Figure l is a vertical section through a power transmission embodying the present invention,

Figure 2 is a section taken along the line 2-2 of Figure l,

Figure 3 is Figure l, l

Figure 4 is a view partly in section of one of the control mechanisms,

Figure 5 is a fragmentary View partly in section of the front brake control assembly,

Figure 6 is a view partly in section of the rear brake control mechanism,

Figure 7 is a diagrammatic view of the hand control mechanism,

Figure 8 is a fragmentary view partly in section of one of the control mechanisms illustrating the pressure release for the resistance pump,

Figure 9 is a fragmentary section illustrating alternative reverse mechanism,

Figure l0 is a view partly in section illustrating one form of control mechanism,

Figure 1l is a diagrammatic view showing the condition of the various elements in the Various settings of the hand control,

Figure 12 is a plan view of a section of the piston used in the rotary valve of the control mechanism,

Figure 13 is a section taken along the line 13-13 of Figure l2,

Figure 14 is Figure l2, and

Figure l5 is a fragmentary section illustrating alternative reverse and low gear mechanism.

Referring now more particularly to the drawings and particularly to Figure l, the power transmission a section taken along the line 3-3 of a section taken along the line 14-14` of upon a hub 34 carried by and forming ay part of the cross wall 2i. A trough 35 may be bolted to the other side of the cross wall 2l, as shown, and the' cross wall is apertured at 36 to communicate oil contained in the trough 35 tothe gears. The housing 31 is apertured as at 37 and a conduit 3d is in communication therewithv to receive oil pumped by the gears 3i) and 33. The as'- sembly just described is the operating pressure pump for the purposes hereinafter descr'bed.

The shaft 2dis provided in the region of the casing 27' with a pair of lateral extensions or protuberances Ait) and "il and, similarly, the casing 27 is provided with a complementary pair of inwardly extending members 42 and: 43. The shaft 2d is provided with a lateral bore 44 andl a longitudinally extending bore 4.5. The casing'Zl7 is provided with a pair of openings 46 and i7 and the protuberances di? and ill, 42 and 43, are so designed as toleave a` slot 4S between them.

Coil springs 49 and Sil are mounted withinv the casing 27, each having one end abutting a protuberance on the shaft 2d and the other end abutting a protuberance on the casing 27, as shown in Figure 2.

The assembly just'described constitutes a torque responsive valve.

Oil supplied to the longitudinal bore 45 in the shaft 2'4 1s communicated thereby to the lateral bore 44 and'thence to the slot 43. Torque applied to the casing 27 will tend to rotate the casing 27 upon the shaft 24 and the exten sions and 41 so as to compress the springs 49 and 50, thus increasing the width of the slots 48, and thus permitting a greater rate of oil escape through said slots in response toV increased torque applied by the drive shaft. Upon a decrease of torque thus applied, the slots 48 will be narrowed under the iniiuence of the coil springs 49 and 50.

- The shaft 24 is also provided with a lateral bore 51 communicating with an annular groove 52 formed upon the periphery thereof A ring 53 having a complementary groove 54 is carried by the shaft 24 and a conduit 55 communicates with a passage formed by the complementary grooves 52 and 54. A similar annular groove 56 is formed upon the shaft 24 and a similar complementary groove 57 is formed within the ring 53, and the shaft 24 is provided with a lateral bore 58 communicating with the passage thus formed. A conduit 59 is provided in communication with this last mentioned passage.

The shaft 24 is likewise provided with an eccentric longitudinal bore 60 communicating with the lateral bore 58 and with afurther lateral bore 61, as shown in Figure 1. The shaft 24 is provided with an annular groove 62 communicating with the lateral bore 61. The shaft 24 is further provided with a lateral bore 63 and an annular groove 64, the lateral bore 63 thus communicating the central bore 45 to the groove 64, as shown in Figure 1. The shaft 24 is provided with a reduced end 65 received within a re-entrant bore 66 formed in the central shaft 67.

The shaft 24 is provided with a collar 68 which is splined for mating with splines 69 formed in the enlarged end of the tubular extension 71 of the clutch cross wall 72.

The numeral 7 4 indicates generally a housing. Integral with the housing 74 is the clutch cross wall 72, the front wall 75, and the rear wall 76.

The front wall 75 is bored out as at 77 to form a cylinder and is provided with a lateral bore 78 communicating the annular groove 62 with the cylinder 77.

In practice, the device will be provided with six similar cylinders 77 and six lateral bores 78, two of which are shown in the section depicted in Figure l. The cylinders 77 are provided with pistons 80. low andare provided with piston shafts 81 affixed to the interior of the pistons and extending through bores 82 in the front wall 75. The outer ends of the piston shafts 81 are enlarged to form collars 83. The wall '75 is provided with bleed holes or bores 84 for bleeding each of the cylinders 77 A sleeve 86 is provided on the shaft 24 having an enlarged collar 87. A coil spring 88 is provided on the shaft 24 between sleeve S6 and the recessed portion 89 of the front wall 7 5. The front wall 75 carries six brackets 90, each mounting a pivoted lever arm 91 having one end engaging the collar 87 and the other end engaging one of the collars 83. The end of the lever arm 91 engaging the collar 87 is appreciably longer than the end thereof engaging the collars 83, and thus provides considerable mechanical advantage.

A yoke 92 is provided engaging the collar 87 and suitably pivoted on a cross shaft 93 for moving the sleeve 86 longitudinally of the shaft 24 and thus pivoting the lever arms 91 to withdraw the pistons 80 to their full forward position to disengage the clutches hereinafter described.

The pistons are reduced in diameter throughout the major portion of their length and the reduced portion is adapted to be received within a bore 94 in the clutch cross wall 72. The piston head 95 is adapted to engage a plate 96 forming a portion of the clutch. The plate 96 is annular in form and is correspondingly engaged by each of the pistons and movably mounted in slots formed in a ring 97. The ring 97 similarly carries a plurality of movably mounted clutch plates 98. A fixed rear wall 99, having a circular opening 100 therein is provided to complete the clutch. The rear wall 99 is preferably formed integral with the housing 74, as shown. The central shaft 67 is provided 80. The plate 96 is externally splined 75 receive the .reduced end of a piston 141. As before,

with an enlarged head 101 and a tubular extension 102 is provided thereon. A ringf103 is mounted upon tubular extension 102 and it movably receives the inner clutch plates 104.

From the foregoing description, it will be apparent that duid under pressure supplied by the conduit 59, the longitudinal bore 60, the lateral bore 61, and the bore 78 will be communicated to the cylinders 77, thus tending to force the pistons 80 to the limit of their forward movement. Coil springs 105 are provided on each of the piston shafts 81, having one end abutting the front Wall 75 and the other end abutting the piston heads 95, and thus the clutch mechanism is spring applied and hydraulically disengaged by the above described mechanism.

The enlarged head 101 of the central shaft 67 is provided with an annular groove 107 cooperating with the annular groove 64, and three bores 108, only one of which is shown in Figure 1, communicate the passage formed by the grooves 64 and 107 to the outlets of a gear pump hereinafter described.

The shaft 67 in the region of the enlarged head 101 is also provided with a collar 109 formed integrally therewith and constituting both a front pump wall and a planet carrier. The collar 109 is provided with three bosses 110 constituting the bearings for a corresponding number of planet gears 111, and a rear pump wall 112 is provided, preferably secured to the bosses 110 by means of studs 113. The rear wall 112 is apertured as at 114 for receiving the shaft 115 carrying the sun gear 116. The shaft 115 is hollow and revolves about the central shaft 67, as shown. An annulus gear 117 is provided on the inner side of the housing 74 cooperating with the planets 111.

A sump is provided constituting the rear wall 7 6 and an interior wall 118, which sump assures that oil maintained therein by means of maintaining the o`l level within the transmission at a suitable height indicated at 119, will be fed to the gears 111 and forced thereby into the outlet 4passage 108. The revolution of the housing 74 will cause the oil in the sump to be forced by centrifugal action to the planet gears 111 peripherally, thus assuring the constant supply of oil to the pump formed by the planet gears and sun gears. The lower portion of the housing which contains the transmission is suitably formed to act as a reservoir 602 for the oil and from this sump oil is admitted to the front pressure pump and to the inlet of the front planetary pump.

It will be apparent that maintaining the oil at such a suitable level (indicated at 119), will also assure a constant filling of the trough 35.

The shaft 115 is provided with an integrally formed plate 120 having a iiange 121 forming a brake drum. shoe 122 provided with a suitable lining 123 is provided for engaging the brake drum. The central shaft 67 is provided with a re-entrant bore 124 for receiving the front end of the driven shaft 125. The central shaft 67 is also provided with a longitudinal bore 126, a lateral bore 127 communicating therewith, and an annular recess 128. A ring 129 is provided on the shaft 67 and has a complementary annular recess 130. A conduit 131 communicates with the passage formed by the recesses 128 and and the shaft 67 in its enlarged portion 132 is provided with a plurality of lateral bores 133 communicating with the longitudinal bore 126.

The enlarged portion 132 forms a front wall 134 and a central clutch wall 135. The front wall 134 is provided with a plurality of bleeding holes 137 corresponding in number to the six pistons and cylinders hereinafter described. The clutch housing also includes a side wall 138 secured to the front wall as by means of the studs 139 and a rear wall 136 is formed integrally with the side wall 138. The structure of the side and end walls in lieu of being as described, can be the same as the structure of the housing 74 above described.

The central clutch wall is apertured as at 140 t? pre erably six of the 141 are hollow and contain a coil spring 142. The p1ston splined in ring 148, which ring 143 is mounted on a recessed portion of the tubular extension 149 of the annulus bearing member 150.

It will be apparent from the above described mechanism that the clutch just described is applied by the pressure of the spring 142 and is disengaged by fluid pressure supplied by the conduit 131, the lateral passage 133 to the cylinders 151.

The shaft 67 is provided with an annular groove 152 which serves to maintain communication between the passages 133 and the passage 126.

The shaft 67 has a reduced portion 155 on which is seated the ring like portion 156 of the annulus bearing member 150. The central shaft 67 is also provided at as the annular gear 159. Preferably, will be three in number.

The plate 166 has a hub-like extension and formed integrally therewith is a sun gear 167 which has a bearing portion 168 riding shaft 125 has a plate-like portion 169 formed integral therewith and having hubs 170 upon a plurality of planet gears 171. be three such hubs and planet gears.

ltflounted upon the driven shaft 125 is a bearing 172 having a plate-like extension 173 which, itself, is provided with a flange 174 upon the interior of which is to brake the annular gear. 175 meshes with the planet gears 171 which in turn mesh with the sun gear 167.

Referring now more particularly to Figure 15, there is shown an alternative embodiment of the mechanism last described. in this the driven shaft 125]) is provided with a plate-lite extension 164th which replaces the eX- tensions 16d and 169 in Figure 1. This extension is provided with a plurality of studs 165b extending forwardly to mount a first series of planet gears 166Z1V and a set of studs 171351 which carry a second series of planet gears 171]; which mesh internally with the first series of planets 1665, and externally with a reverse annulus gear 1Mb. The central shaft 67h carries a ring 149]; with splines for the inner plates 147b of the rear clutch. At its rear end shaft 67]; has a driving sun 157b which drives the rst series of planets 166b. A brake drum is supported centrally on shaft 67h by a bearing hub 168b which also carries a reaction sun gear 167b meshing with the second series of planet gears 171i). Preferably there are three planets in each of the said series. A brake 130 serves to hold the reverse annulus gear 17417 stationary. A bearing member 600 is provided upon the shaft 125b and carries a plate 691 which mounts the annulus 174i). Referring now more particularly to Figure 9, there is shown an alternative embodiment of the mechanism last described in which the annulus mounting a corresponding number of planet gears and 171e. The planet gears 166e mesh with the annulus 1590 and the sun 15711. The plate 16911 is provided with a plurality of studs 191, each mounting a planet gears 191 and 192 are again preferably three in number.

The planet gears 171g mesh with the annulus gear 175g and with the planet gears 192. The planet gears 192, in turn, mesh with the sun gear 167g. A brake 162 is provided for braking the annular gear 159:1 and a brake 177e is provided for braking the annulus 175g.

The operation of the above described device is as follows:

Assuming torque is applied to the drive shaft 20, this torque will be applied through the casing 27, springs to the shaft 24. The torque shaft 24 is communicated through the splines 69 to the the torque thus applied will be transferred to the annu annulus bearing r ing the driven shaft at a direct 1:1 ratio.

Assuming that both of the clutches above described are disengaged, which is accomplished by applying Huid annulus gear 117 is thus rotated,

are worked. Through controls hereinafter described, the brake 122 is applied, thus locking the sun gear 116. This causes the planet gears 111 to tra el forwardly about the sun 116 and thus transfers the torque to the planet carrier 109 and thence to the central shaft 6?. The central shaft 67 is, however, driven at a rate which is at a ratio of 1.5 :1, the rate of the shaft 24, due to the constants of the annulus gear and planet gears.

The torque thus applied to the central shaft 67 is again transferred to the wall 134, the wall and the wall 13S which, together, form the housing of the second clutch. The second or rear clutch formed by the plates 1414,

trols hereinafter described, In this condition, the planet gears 166 are worked, thus driving the planet carrier 164 forwardly, but again at a reduced rate of approximately 2.5rl, with respect to the rotation of the central shaft 67. As the planet carrier 164i is integral with the driven shaft 125, a combined ratio of approximately 3.75 is obtained.

From the foregoing description, it will be apparent that if the front clutch is engaged, the front unit will be bound together, thus eliminating the 1.5:1 mechanical advantage obtained through working the front planetary gearset, and if the rear clutch is disengaged, a gear ratio of 2.5:1 is obtained. This condition approximates a conventional second gear.

It will be likewise apparent that if the rear clutch is engaged and the front clutch disengaged, the rear unit will be bound together, thus eliminating the 2.5:1 advantage obtained therein and leaving only the 1.511 advantage obtained in the front unit, a condition which approximates a third gear with a 1.5 :l gear ratio.

As hereinabove described, the engagement of both clutches conditions the entire device for rotation as a unit with a direct 1:1 ratio.

A fully automatic operation with variable gear ratio can also be achieved by the above described device. In this condition, the rear clutch formed by the plates 144, 145 and 147 is engaged, the front clutch is disengaged and the brake 122 is disengaged. The torque will thus be applied from the shaft 24 through the housing 74 to the annulus gear 117. This will tend to drive the planet gears 111 forwardly and the sun gear 116 backwardly. ln this condition, the pump formed by the sun gear and planet gears pumps oil into the passages 108 and out through the conduit 55 and through the slot 48.

The conduit 55 is shown for use in connection with a set of controls yet to be described. If the control is desired to be achieved through the torque responsive valve comprising the housing 27 and associated mechanism, the conduit 55 may preferably be closed at the port 296. ln this condition, the escape of oil from the passage 45 is entirely dependent upon the opening of the slot 48, due to the relative movement of the housing 27 and the shaft 24. As this relative movement is dependent upon the torque applied and the amount of compression of the springs 49, increased torque will cause a wider escape to be presented for the oil and therefore less resistance to the pumping of the gears. In this condition, the engine is permitted to turn at a much greater rate than is the planet carrier 109 driven forwardly, the ratio being entirely dependent upon the relative torque applied. lf the resistance is increased by a decrease in the opening 48, the pumping of the gears will be rendered more difficult, in which condition the planet carrier will travel forward at a gradually increasing speed until it approaches a condition wherein the pump action is reduced to a minimum. in this condition, the planet carrier is driven forward at a rate approximating a third gear ratio or higher. The driving of the planet carrier, as above-described passes torque to the driven shaft through the rear unit which is locked together as a unit by the rear clutch.

Reverse gear is 1 by using the sprag 177. The locking of the sprag through controls to be herein described brakes the an nulus 175. Torque then applied through the central shaft 67 is transferred from the sun gear 157 through the planet gears 165 to the annulus gear 159, the plate 160, to the sun gear 167 which drives the planets 171. As the annulus gear 175 is held by the sprag, the planet carrier 169 which is integral with the driven shaft 125 is caused to be driven backwards. This reverse drive is obtainable in any condition of the mechanism described in which the brake 162 is not applied and the rear clutch is disengaged, thus aiording a reverse in which there are obtainable two xed gear ratios depending upon the operation of the brake 122 and the front clutc An infinite reverse gear ratio is also provided by disengaging both the front clutch and the brake 122 and thus causing the oil pump to turn.

Referring now to the device shown in `ldigure 9, the operation of the device is in all respects similar to the operation of the device shown in Figure i, with the exception of reverse. 1n this case, reverse is obtained by applying the brake 177e the rear clutch being disengaged and the brake 162 disengaged. This brakes the annulus gear 17 5a and drive is imparted through the sun gear 167a, which is integral with the central shaft 67, to the planet gears 192, thence to the planet gears 171a to the planet obtained with the device shown in Figure t carrier 169a. As the annulus gear 175a is held, the planet carrier 169e is driven backwards and hence reverse rotation is imparted to the driven shaft 125e.

In order that the driver will have immediately under his control mechanism for establishing the various conditions above described, there is provided a control mechanism shown in Figure 10. This control mechanism includes a control cylinder 200, which cylinder contains a piston 201 having a piston shaft 202 on which is mounted beveled gear 203. A second beveled gear 204 is provided meshing with the gear 203 and having a shaft 205. The shaft 20S is provided with an operating handle 206 and an indicator 207 preferably disposed adjacent the steering wheel of the vehicle. The indicator 207 is provided to indicate the condition of the controls and is provided with a dial 208 provided with indicia adapted to indicate the conditions of reverse, neutral, automatic drive, iirst, second and third, and 1:1 ratio and brake. (See Figure 7.)

Figure l2 illustrates a portion of the piston 201. The piston is provided with a plurality of recesses 209 upon one side of a slot 210 and a corresponding number of recesses 211 upon the other side of the slot, but spaced so as to provide alternately a recess 209, a solid portion 212, respectively aligned with a solid portion 213 and a recess 211, as shown in Figure 12. The cylinder 200 is provided with a plurality of openings 214, each of which is joined by a conduit 215 to a header 216 which communicates with the conduit 38 leading to the outlet of the pressure pump. The cylinder 200 is likewise provided with a plurality of openings 218 which drain to the oil sump. It will be apparent from the above description that a suitable turning of the piston 201 will dispose one of the solid portions 212 or 213 so as to cover the openings 214 or 218, or, alternatively, to uncover such openings by means of a recess 209 or 211. The cylinder 200 is provided with a plurality of openings 219 which are in communication with conduits 220, 221, 222, 223 and 224. Thus, the passage of oil from the conduit 38 to any of the conduits 220 to 224, inclusive, can be regulated by the control handle 206 and similarly any of these lines can, when desired, be drained.

A cylinder 228 is provided having a piston 229 disposed therein with a coil spring 230 interposed between one end of the piston and the end of the cylinder 228 and a coil spring 231 disposed between the other end of said piston and the other end of the cylinder. The piston 229 is provided with a piston shaft 232 having a collar 233 therein adapted to be engaged by a yoke 234. The piston shaft 232 is also provided with a second collar 235 and a coil spring 236 may be disposed upon the shaft 232, as shown. The spring and collar 236 and 235 are also adapted to be engaged by the yoke 234 for retraction of the piston 229 The cylinder 228 is provided with an opening 237 to which is attached the conduit 220, an opening 238 to which is attached the conduit 221 and an opening 239 to which is attached the conduit 222. The piston 229 is provided with three annular slots 240, 241 and 242 disposed as shown in Figure 10. The cylinder 228 is also provided with openings 243, 244, 245, 246, 247 and 248. Openings 246, 247 and 248 are drain openings, whereas openings 243, 244 and 245 have conduits, each indicated by the numeral 260 and each communicating by a header and conduit not shown, to the conduit 38. The drain openings may also be provided for drainage to the oil sump.

The cylinder 228 is also provided with openings 249, 250 and 251 of greater lateral extent than the slots 240 to 242 and communicating, respectively, with conduits 252, 253 and 254. From the mechanism above described, it will be apparent that upon moving of the piston to the right or left within the cylinder 228, communication can be established from the conduit 220 to the conduit 252 or, alternatively, the conduit 220 can be closed off, and one of the conduits 260 opened to apply uid pressure to the conduit 25 In the event the piston 229 is moved to the left, conduit 221 will be closed, conduit 260 opened, and oil under pressure applied to the line 253. In the event the of the piston 300 The position of piston 300 is in turn piston is moved to the right, conduits 260 and 221 will be dependent upon the relative positioning of the shafts 305 closed and the drain 246 opened. and 308. Conduit 272 is connected to the conduit 55 In the event of the movement of the piston to either which is an outlet for the planetary gear pump With the right or left, conduit 222 will be closed and one or the hand brake off and shaft 285 rotated clockwise valve 274 other of the drains 247 and 248 opened, thus draining is moved to the left and conduit 272 is open to conduit the line 254. The yoke 234 is operated by a shaft 261 254 With throttle-connected arm 234 intermediate of controlled by the throttle pedal of the engine in such a its full open and fully closed positions, valve 229 is cenmanner that clockwise rotation of the yoke corresponding teied and conduit 254 open to conduit 222, and, with roto an opening of the throttle, and counterclockwse rotatary valve 261 in position for automatic drive, conduit tion corresponding to a closing of the throttle The l5 222 is open through port 296 to conduit 295. The flow above described mechanism provides for a free wheeling through conduit 55 then depends on the openings at ports effect when the throttle is closed, and an automatic shift- 293 and 294. ing from high to third gear on a sudden full opening of Shaft 365 is mounted so as to move to the right (Figthe throttle, as hereinafter described. ure 10) upon closing of the throttle 605, whereas shaft A cylinder 264 is provided having openings 265, 266 358 moves to the left upon increased turning of the driven and 267 The conduit 253 is attached to the opening shaft 125. Thus a closing of the throttle tends to move 265 and the conduit 254 is attached to the openinfy 266 the piston 3h0 to the left and an increased turning of the wnereas the conduit 223 is attached directly to the opendriven shaft also tends to move the shaft 328 to the left. ing 267, as shown. The gear iatio of the transmission when in automatic The cylinder 264 is also provided upon the other side drive is decreased upon an increase, as hereinafter oewith enlarged openings 268, 269 and 270. A conduit 271 scribed, to the resistance to the passage of oil fiom the is attached to the opening 268, the conduit 272 to the conduit 222. As a movement of the piston G to the opening 269, and a conduit 273 to the opening 270. left tends to close the openings 293 and 294 and increase A piston 274 is provided in a cylinder 264 which piston the resistance to the escape of such oil, it follows that a is provided with annular slots 275 276 and 277 as shown, 30 movement of the p ston 360 to the left decreases the gear The piston carries a piston shaft 278 which passes through iatio and places the transmission in higher gear It will an end opening 279 and carries thereon a coil spring 280 be apparent that such change in gear iatio is automatically interposed between the right end of the cylinder and the accomplished, either upon a closing of the throttle or an right end of the piston, as shown. A bleed hole 281 may increased speed of the vehicle, and vice versa. At lowei` be provided in the left end of the cylinder. The shaft 273 speeds the Operator may Sometimes find that the hydraulic is provided with a m31131- 232 and a coil sp1-ing 282)- A contiol thus described is rough in operation, tending too yoke 284 is pivotally mounted on a shaft 285, connected Suddenly l0 aIlly reSlSianCe t0 the reSiSiahCe Pump A to and operated by a hand brake, 610, adapted to engage ne adjustment may, however, he made by the needle the Spring 233 and collar 282 and move the piston 274 to Valve 298 to overcome this defect. The needle valve 298 the right, thus closing communication between the conmay he Sniielhly Plaeed Wihin reach 0f the Operator 0f duits 253 and 271, between conduits 254 and 272, and the vehicle or Service men for making this ne adiush conduits 223 and 273, and at the same time draining the nientconduits 271, 272 and 273 through drain Openings 236, The operation of the above described device is as 237, and ess. follows:

A Cylinder 290 may be provided having Openings 291 The conduit 252 is attached to the conduit 59 provided and 292 on one side and drain openings 293 and 294 on for the application 0f Oil undef Pressure from the Pump the other Side. A c0ndu1't295is provided having one end to the front clutch. The conduit 271 is provided for the communicating wi h a drain opening 296 in the cylmder Operation of the hydraulic cylinder hereinafter described 20g and the other end commumcatmg Wlth the Opening operating the front brake 122 The conduit 272 is in 292 The condult 295 1S provided Wlth a branch 297 50 communication with the conduit 55 and thus controls the leading to needle valve 298 and thence through conduit escape 0f fluid Under Pressure from the Pump fnrnied by 299 to the opening 291. A piston 300 is provided within the front Planetary geafseig The Condnii 273 1S in Coin' the cylinder 29@ having reduced portions, as Shown at munication with the conduit 131 and thus controls the 301 and 302 The piston 390 Carries a plston Shaft 303 application of the rear clutch. The conduit 224 is romoumed for Shdm., movement as at 304 A slide shaft vided for the supply ofoil under pressure to the hydraulic 3135 sultab1y mounted as at 305 and 307 is provlded com mechanism for controlling the rear brake 162 as hereinnected to the accelerator or throttle pedal of the vehicle afier desffihed- The driven shait 125 is provided with a conventional Referring HOW i0 Figure il: there is Shown a i505( ile centrifugal mechanism 606, working only in forward dnve lustrating the condition of the transmission in the various and not acting when the toilshaft is reversing, to which, is Seiiings 0f the CCnirOl 295 When lvhe engine iS Shui ffii, operably attached a shaft 308 mounted for sliding movethe COIICOII referred i0 21S dead engine, H0 pressure ment as at 309 in response to movement of the centrifugal will be built up by the front pump and communicated to mechanism in such manner that the shaft 3198 moves to the line 38. As the front clutch is released by pressure the left on increased revolution of the driven shaft 125, supplied from the line 38 through the cylinder 26d, the and to the right on decreased revolution of the shaft 125. conduit 220 and the Conduit 252 commumcatmg with A lili 31h iS PiVOily mounted 0H the Shaft 305 aS at the conduit 59, the fiont clutch will be engaged under the 311 and intermediate the ends thereof is provided with force of the C011 sprmgs 1115 The from blaue m11 be an enlarged Portion 312 having a Slot 313 therein adapted olf, being hydraulically applied as hereinafter described, i0 reCeiVe a Pin 314 Carried by the Shaft 303 TOWard dependent upon oil under pressure from the conduit 38 ilS lOWer end, he link 310 1s Provided With a SeCOnd en- 70 cylinder 200, conduit 221 and Conduit 271 The resistlarged POrlOn 31 having a 510i 315 thereih admitted i0 ance pump formed by the front planetary gearset will be receive a PD 317 Carried l)y I[he Shlft 30fiidle. The rear clutch being spring applied by the coil Assuming that the conduit 295 is in communication springs 142 and released upon the application of oil under with oil to be drained from conduit 222, the oil under pressure through the conduits 131, 273, 223 and cylinder pressure will pass through the opening 292 into the cyl- 200, and conduit 38, will be engaged. The rear brake 11 being, as hereinafter described, spring applied and hydraulically released under the force of oil under pressure supplied by the conduit 224, cylinder 200i and conduit 3S will be engaged.

In this condition, therefore, both of the clutches are engaged and the main brake is on. It will be apparent that the engine cannot be started in this condition as the transmission is locked to both the drive and driven shafts and a brake is applied. This presents a safety factor assuring that the engine cannot accidentally be started by careless persons or children.

In order to start the engine, the operator must first apply a hand brake. The hand brake is shown in Figure 6 where there is illustrated the hydraulic mechanism for releasing the main brake and the associated mechanism.

The hand brake operates a rod 32) which is slidably mounted as at 321 and has pivoted thereto a link 322. One end of the link 322 has a cam 323 adapted to engage the brake post 324 formed on the brake shoe 162. The other end of the link 322 is pivoted to a link 325 which is itself pivoted to a link 326, which link 326 is fixedly connected to the cross shaft 93 which carries the yoke 92. Thus a movement of the rod 320 to the left (Figure 6) will engage the yoke 92 with the collar S7 of the sleeve 86 which, in turn, will pivot the lever arms 91 so as to retract the pistons 8i) and disengage the front clutch. At the same time, if conditions are appropriate, the brake 162 will remain engaged, due to the action of the cam 323.

A shaft 327 is provided carrying a cam 328 adapted to engage the other side of the post 324 and prevent engagement of the brake 162. Shaft 327 is operatively connected by means not shown to a push-tow button 329, preferably located on the dashboard in` a position for convenient access of the operator. Alternatively, the cam 3S-3 may be actuated through suitable connections 664 by a handle 604A7 Figure 6. The push-tow button is engaged to force the cam 388 against the post 324, as shown in Figure 6, in either towing or in push or tow start. In towing, the engine, of course, dead and the conditions the sarne as above described with respect to dead engine, but the hand brake is engaged to move the shaft 320 to the left and disengage the front clutch, as above described, and at the same time, the push-tow button is engaged to engage the cam 328 with the post 324 to disengage the brake 162. Preferably, the push-tow button is actuated prior to the putting on of the hand brake.

in either push or pull start, the conditions will be the same as for towing, with the exception that the hand brake will not be applied so that the yoke 92 will not be engaged with the collar 87 to disengage the front clutch and thus the engine will be turned over by the forward movement of the vehicle.

The condition of the mechanism in automatic drive has been described above, as well as the condition in reverse. ln neutral, the front clutch is oif; the front brake is off; the resistance pump outlet, the conduit 222, being open to the drain 218; the rear clutch is engaged and the rear brake is on. The hand brake is initially on for the starting above described, but is then taken off.

For hill braking with this transmission, two types are provided: the fixed gear ratios, any one of the four gears is available for turning the engine to provide braking; however a second type of hill braking, depending on the resistance pump is afforded with the handle 266 turned into the portion marked brake in Figure 7. In this condition, the engine is not relied upon for the brake effect, but rather the resistance afforded to the resistance pump. In other words, the front clutch is disengaged and varied resistance applied to the output of the resistance pump by regulating the amount of opening provided at 218.

Further, two conditions of this pump braking are possible, one in which the rear planetary is bound as a unit by engaging the rear clutch in which the driven shaft 125 and the central shaft 67 will revolve as a unit, and in the other of which the rear planetary is working, the clutch being disengaged, the rear brake 162 is engaged, thus giving a 2.5 :l ratio of drive between the driven shaft 125 and the central shaft 67. In any condition of pump braking, the brake 122 is applied. It will be seen that the resistance pump functions as a clutch but the progressive clutching action embraces all the members of the planetary assembly including any other members in direct connection with the said assembly. The member connected with the driven shaft is not only clutched to the member connected with the drive shaft but is also clutched to the said third member which is provided with associated braking means. If the said braking means is engaged and the third member held stationary thereby, then the said driven shaft will also be braked to a degree in accordance with the degree of fluid clutching which is present. If the liow from the pump is completely unrestricted and provided with a wide-open escape then the driven shaft will turn the engine as a brake in the reduced ratio which is provided by the planetary assembly.

When the pump is completely closed, locking of the gears forming the pump becomes practically complete and the engine, the drive shaft, the planetary assembly and the driven shaft are all locked together.

The above feature is not one of engine-braking and if disconnecting means such as a iluid clutch were installed, between the drive shaft and the engine, the gear-locking described would still be operative. When the operator of the vehicle applies the said braking means and then restricts the said out-flow, he variably restrains the rotation of the gears forming the said pump and variably restrains, at the same time, the rotation of the said driven shaft.

A free wheeling effect, as well as a kickdown into a lower gear is also achieved by this invention. For free wheeling, by means of the device shown in Figure l0, the throttle is released, the yoke 234 is pivoted in a counter-clockwise direction engaging the spring 236 and the collar 235, and moving the piston 229 to the right, thus opening the drain openings 246 and 248. This results in a draining of the conduits 271 and 272 so that very little resistance is offered to the resistance pump and the front brake is disengaged. At the same time, the opening 244 is opened, applying power to the conduit 252 and consequently disengaging the front clutch, thus freeing the engine.

For a kickdown, a rapid change from top to third gear for quick acceleration, the throttle is quickly depressed beyond its normal full open position, thus pivoting the yoke 234 in a clockwise direction and moving the piston 229 to the left. In this condition, the front clutch is disengaged by power applied through the opening 243, the front brake is applied by power supplied through the opening 245, the resistance pump is drained through the opening 247. As the top gear requirements differ from the third gear requirements only in the disengagement of the front clutch, and the engagement of the front brake and as these requirements have been met by a proper positioning of the piston 201, the device is thus shifted from top to third gear from which it will return to top gear immediately upon release of the throttle from the extreme position.

As stated hereinabove, the front brake is put on by applying oil under pressure through the conduit 271.

Referring now more particularly to Figure 5, a preferredV embodiment of this construction 1s shown including the brake shoe 122, a post 332 to which is atiixed by adjustable nuts 333 a piston shaft 334. A cylinder 335 is provided housing the piston 336 to which the shaft 334 is pivotally connected. A coil spring 337 is provided between the piston head and the open end 338 of the cylinder. The piston seats upon a shoulder 339 formed in the cylinder and is provided with an annular groove 340 and a fluid passage 341 communicating the cylinder head 342 75 with the annular groove. `The Vconduit 271 has two the conduit 271 cannot pass the check valve 347 but must grabbed the brake 1s achieved, however, as the check valve 347 and the power opening 356 to which is connected the header 216. Thus the sprag 177 is operated by a proper annular Vgroove 378. The cylinder head 384 is provided with an opening 385 to which is attached a conduit 386. The conduits 383 and 386 may be joined and connect 387 are so designed that pressure is applied to the conduit 387 only 1n top gear and the conduit 387 is otherwise open to drain.

The cylinder 376 also houses a coil spring 391 mounted upon a rod 392 carried by the piston 377. The rod 392 extends through an opening 393 in the cylinder 358 and is adapted in one position to seat in Ythe annular groove 361 in the piston 359.

The operation of the last described mechanism is as follows:

With the hand control 266 set in top drive, pressure is admitted from the conduit 38 leading from the pressure 336 into the head of the cylinder 376, thus tending to move the piston 377 downwardly. As the piston moves spring 37E is controlled to prevent grabbing of the brake by the needle valve 369 as the check valve 368 prevents passage of the iluid through the branch 366.

The springs 3 and 391 are selected so that the spring 391 is in all cases strong enough to disengage the end of the shaft 392 from the groove 3M when pressure is released from the conduit 336.

Referring now more particularly to Figure 4, there is shown a control designed to incorporate in one mechanism the cylinders 228 and 264, and associated mechanism. In this embodiment, a cylinder 4% is provided end of the cylinder and with a collar 304. A yoke 495 is provided on a shaft dilo operated by a hand brake A shaft 37 is provided mounting a yoke 433 adapted to engage the left end of the piston 4M. The shaft 407 is preferably attached and operated by a pedal similar to a conventional clutch pedal. The cylinder is provided with openings 4h39 and 4M) to which are attached conduits dit and @i2 which are joined, communicating with the pressure line 35 by conduit 2.6i?. The cylinder lt? is further provided with an opening 413 to which is attached the conduit 22h and an opening 249 is provided to which is attached a conduit 252. Like numerals in Figures 4 and 10 serve like functions.

The valve piston H1 is worked fully to the left by the arm -ftS operated by the hand brake and Worked fully to the right by arm 433 operated by the clutch pedal described above. Spring 439 operates to move piston lill to its center position where it is held by detent ball 437 as shown in Figure 4.

The cylinder 4.6i? is further provided with a pair of drain openings 4M and i5 and an opening die to which is attached a conduit 221. An opening 25:1? is provided to which is attached a conduit 27M which replaces the conduits 253 and 271 and serves a function similar to the conduit 271 The cylinder is further provided with drain openings 417 and 41S and an opening 419 to which the functions of conduits 254 and 272.

A pair of drain openings 420 and 421 are provided respectively.

and an opening 422 is provided to which is attached the conduit 223. An opening 423 is provided to which is attached a conduit 273.

The cylinder is further provided with openings 424 and 425 to which are attached conduits 426 and 427 which are joined to the conduit 260 which communicates with conduit 33 of the front pressure pump. An opening 423 is provided to which is attached a conduit 224. An opening 420 is provided to which is attached a conduit 2240.

The piston is provided with annular recesses indicated generally by the number 430.

A box like enlargement 431 is provided on the cylinder which is bored as at 432 and 433 to receive the springs 434 and 435 and balls 436 and 437. An annular groove 43S is formed in the piston 401 as shown. A coil spring 439 is interposed in the cylindersurrounding the shaft 402 and abutting the end of the cylinder on one end and the piston head on the other end, as shown, and a bleed hole 440 is provided in the cylinder 400.

The operation of the above described device is as follows:

in its normal position, the piston is positioned as shown in Figure 4 under the force of the spring 439 and retained therein by the ball or detent 437 seating in the groove 438. ln this condition, each of the conduits 220, 221, 222, 223 and 224 is open, each communicating with its associated annular recess 430 and communicating any pressure that may exist in said conduit through to the conduits 252, 271er, 272a, 273 and 22401, in this condition, the operation of the Various controls will depend upon the setting of the rotary valve formed by the cylinder 200 and piston 201, depending upon the position of the handle 206.

Upon actuation of the hand brake 601 to turn the shaft 406 so that the yoke 405 engaging the collar 404 is turned in a clockwise direction, the piston is moved to the left (Figure 4) to a position in which the ball or detent 436 engages within the groove 438. In this position, each of the openings 413,. 416, 419, 422 and 42S is closed, the opening 409 is open, and power from the conduit 35 is passed to the conduit 252, the drain 414 is open, and consequently the line 271a is drained. The opening 417 is open and consequently the conduit 272a is drained. The drain 420 is open and consequently the conduit 273 is drained. The opening 424 is open and consequently power is` applied by the conduit 260. in this condition, power is supplied by the conduit 252 to the front clutch to disengage this clutch. The line 271m leading to the front brake is drained and this brake disengaged by the spring 337. The conduit 272:1 is drained and hence the conduit 55 is drained, thus freeing the resistance pump. ln this condition, the conduit 273 is drained, thus draining the conduit 131 and permitting the rear clutch to engage under the force of the coil springs 142. Finally, the conduit 22451 is supplied with iluid under pressure from the conduit 33 to disengage the rear brake 162. The hand brake is simultaneously moving the shaft 320 to the left, thus engaging the cam 323 with a post 324 and applying the brake completely under the control of the operator, as the shaft 362 slides through the opening 450 in the post 424.

As hereinabove described, the operation of the hand brake has simultaneously rotated the shaft 93 to engage the yoke 92 with the collar 87 to disengage the front clutch. Thus, in this condition, the vehicle is held and the engine is freed Vior starting.

After the hand brake has been thus applied to condition the device for starting the engine and the engine has been started, the hand br ke is released. The detent 436, however, will hold the piston 401 as placed by the hand brake until the clutch pedal 606 is depressed to rotate the shaft 407 in a counter-clockwise direction to engage the on the other. In construction spring s 16 yoke 40S with the end of the piston completely to the right.

The cylinder 400 is provided with a shoulder 451 to limit the movement of the piston 401 to the right. When the piston has thus been moved fully to the right, the same condition will prevail as when it was moved fully to the left, with the exception that the opening 410 replaces the opening 409, the drain 415 replaces the drain 414, the drain 41S replaces the drain 417, and the drain 421 replaces the drain 420, while the conduit 427 replaces the conduit 426. The operator may then release the clutch pedal which permit-s the piston to move slowly to the left under the inuence of the spring 439 to restore the initial setting wherein the controls are dependent upon the setting of the handle 206. The dashpot action of bleed 440 steadies said movement.

Referring now to the device shown in Figure 15, the operation is as follows. For low gear the rear clutch is free and brake 16217 holds stationary the drum 158b and the reaction sun 167i). Driving sun 157b rotates planets 166b backwardly. These in turn rotate planets 171b forwardly on sun 1671 and planet carrier 1'64b and driven shaft b are rotated forwardly. In reverse, the rear clutch is free, brake holds the reverse annulus 17417 stationary. Driving sun 17511 rotates planets 16612 backwardly and planets 171b forwardly to carry the planet carrier and driven shaft 125k backwardly as planets 171b travel on the stationary annulus 17 4b.

Referring now more particularly to Figure 8, there is illustrated an alternative control method utilizing the resistance pump to soften the action of the front clutch and reduce the wear on the front clutch and while there will be described this device in connection only with the front clutch, it will be understood that a similar device can be utilized with respect to the rear clutch? In this embodiment, the oil is not permitted to freely escape from the opening 48 of the torque valve, but this opening is communicated by a ring 600, or otherwise, to a closed conduit 500,

to force the piston which conduit rs communicated to a new section 200i; of the cylinder 200, which section is provided with an opening 501 to which the conduit 500 is attached. The piston 201 is in this case provided with an annular groove 502 and a recess 503, thus affording mechanism for either shutting oi the conduit 500 or fully draining it. The conduit 55 constituting the other outlet for the'resistance pump is taken to a new section 400b of the cylinder 400, which section is provided with an elongated opening 505, to which the conduit 5S is attached, a pair of drain openings 506 and 507 and an opening 508 to which a conduit S09 is attached. The piston 401 is provided with an annular recess S10. n

The conduit 509 is connected with an opening 511 in the new section 200b of the cylinder 200, which section is also provided with a pair of drain openings 512 and 513 and with a further opening 514 to which is attached a conduit 515. The piston 201 is provided with an annular slot 516 and a pair of recesses 517 and 518. The dashpot comprises a cylinder 519 having a drain opening520 and a piston 521.

The cylinder 519 has a reduced with an inwardly extending annular shoulder S23 and an opening 524. A ball 525 is resiliently biased'towards opening 524 by a coil spring 526. The cylinder is also provided with a bleed hole S27 and a coil spring 540.

The conduit 515 is branched into conduits 5,28 and S29, branch 52S communicating with the cylinder at 534 and branch 529 being provided with a check valve S35 and communicating with the cylinder 519 and 536. The entire mechanism just described is preferably submerged in the oil sump to prevent pumping of air.

The rate of movement of piston 521 in the control device shown in the lower portion of Figure 8 depends on the relative resistance offered to'uid ow by spring-biased ballV S35 on the one hand and by the needlecontrol 527 540 need only be portion 522 provided 516, the recess 518 and conduit 515 to the dashpot which when the piston 401 is in either extreme positionlto the left or right, the openings 506 or 507 are provided for this purpose.

As the dashpot slowly builds up resistance to the pump, the torque valve then becomes operative, the escape from the Vtorque valve will be fully open for automatic drive, or fully shut for all other conditions.

The opening 513 is so positioned so as to provide a variable restriction to the outlet which, asy explained above, is utilized in hill braking. l

The above described device can be simplified by the the various pump escape conduits and the valve 298.

With this construction the hand brake lever operating the shaft 466 and shaft 93 is used to cam off the front clutch to start the engine. This also moves piston 401 to the left (Figure 4) to open up opening 469 to supply I neutral) the driven shaft 125 is held.

The front clutch remains ot as in neutral, oil under 'so the front clutch remains disengaged while the com duit 271 is drained through opening 415 so that the front brake is olf. The engine is thus free.

if the indicator 207 is now moved to irst gear the rotary valve or piston Zl is moved admitting pressure converter; free wheeling when the clutch pedal is depressed; positive disconnection of the engine for starting; no creeping; the hand operated cam 328 for holding What i'sclaimed is: l. In a power transmission in a motor vehicle, in combination: a drive shaft; a driven shaft; a uid pump supavana-rs I9 cylinder and said hydraulic mechanism to receive said fluid pressure.

3. A power transmission as set forth in claim 2 wherein: said manually operated lever is operable to apply said brake irrespective of whether uid pressure or drainage is being applied to said cylinder.

4. A power transmission as set forth in claim 2 including: a manually operated mechanism operative independently of the supply of fluid pressure to said cylinder and of the manually operated lever to prevent engagement of said brake.

5. A power transmission as set forth in claim 2 including: a third shaft operably connecting said drive shaft to the source or' power; a front clutch serving to connect said third shaft to said drive shaft; and means operated by said manually operated lever and operable on operation of said lever to disengage said front clutch to free said drive shaft from said third shaft.

6. A power transmission as set forth in claim 2 including: a third shaft operably connecting said drive shaft to 20 the source of power; a front clutch serving to connect said third shaft to said drive shaft; a cylinder and a piston operatively associated with said front clutch, said cylinder receiving fluid pressure from said fluid pump to disengage said front clutch; said valve means having a neutral 25 position whereby sa d front clutch is disengaged, rst said clutch is engaged, and said brake is engaged irrespective of operation of said manually operated lever.

7. In a power transmission in a motor vehicle, in combination: a drive shaft and a driven shaft; a planetary gearset having sun gear, planet gears, a planet carrier and an annulus gear; said drive shaft being connected to a member of said gearset; braking means to check rotation of another member of said gearset and providing a reaction gear; clutch means operative to lock the members of said planetary gearset for unitary rotation, said clutch means serving to connect said drive shaft tot said driven shaft; a fluid pressure pump; hydraulic means associated with said clutch and adapted to receive pressure from said pump to dsengage said clutch; spring means normally '40 biasing said clutch means to engaged position; a manually operated member; and means operably connecting said manually operated member with said clutch means to mechanically disengage said clutch.

8. In a power transmission, in combination; a drive shaft adapted to receive torque from an engine; an intermediate shaft and a driven tailshaft; a pump supplying iluid pressure; a front planetary gear assembly having a sun gear, planet gears, a planet-gear carrier and an annulus gear; a direct drive from said drive'shaft to the annulus gear in said assembly; braking means to hold stationary the sun gear in said assembly; a direct connection from said carrier to said intermediate shaft; front clutch means to connect said drive shaft to said intermediate shaft for unitary rotation; a rear planetary assembly having a sun gear directly driven by said intermediate shaft, planet gears driven by said sun gear, planet-gear carrier means directly connected with the said driven tailshaft, and a reaction gear on which said planet gears work to rotate said latter carrier means in low forward drive; braking means .to hold said reaction gear stationary; spring means normally biasing said latter braking means to engaged position and hydraulically operated means serving to restrain said latter braking means from engagement; clutch means serving to connect two members of said rear assembly and thereby lock said assembly to provide unitary rotation; said latter clutch means serving to connect said intermediate shaft and said driven tailshaft in a direct drive; spring means normally biasing said latter clutch means to the engaged position; hydraulically operated means serving to restrain said latter clutch means from engagement when the gears of said gear assembly are working on one another in low ratio drive; and manually operated means serving mechanically to restrain said rear braking means f 2o from engagement Awhen said huid pressure is not avail# able.

9. A power transmission as set forth in claim 8 including; spring means normally biasing said front clutch means to the engaged position; hydraulic means operable to restrain said front clutch means from engagement; spring means normally biasing rst-said braking means to the disengaged position; hydraulic means operable to apply the first-said braking means; another reaction gear in said rear vassembly with which the said rear planetary gears work to provide reverse rotation of their supporting carrier means which is directly connected with the said driven tailshaft; and braking means serving to hold the latter reaction gear stationary.

10. A power transmission as set forth in claim 9 including; manual means for controlling the hydraulic operation of the said front clutch means, the said front braking means, the said rear clutch means and the said rear braking means; and means for manually controlling the operation of the braking means associated with the latter said reaction' gear to provide reverse drive, whereby selectively may be applied four forward gear ratios and two reverse gear ratios between said drive shaft and said driven tailshaft.

ll. A power transmission as set forth in claim 10 in which; gears in said front gear assembly are enclosed to form a fluid pump; an inlet and an outlet for said latter pump; a spring-biased valve automatically operated by uid pressure and serving to control said outlet; restriction of said outlet serving to resist the rotation of the gears forming said pump, thereby varying the ratio of the drive between the said drive shaft and the said intermediate shaft; and means to control the rate of closure of said outlet.

12. A power transmission as set forth in claim 10 including; means to manually disengage the said front clutch, said disengagement serving to free the engine when the said front braking means is also disengaged by its associated spring means.

13. A power transmission as set forth in claim 10 including; a movable valve operable in one position to supply Ypressure to the hydraulic mechanism which restrains the said front clutch from engagement thus serving to free the engine from its drive when the said front braking means is also disengaged by its associated spring means; and a foot pedal operably connected with the said valve to move said valve into the said position.

14. In a power transmission, in combination; a shaft receiving torque from an engine and a driven shaft; a planetary gear assembly; a sun gear in sa'd assembly directly driven by first said shaft; a first series of planet gear meshing with said sun gear; a second series of planet gears meshing with said first series; a planet carrier supporting both said series of planet gears and directly connected with said driven shaft; an annulus gear meshing with said second series of gears; a rotatable member integral centrally with a second sun gear and fitted peripherally with a brake drum; said second sun gear meshing with said second series of planet gears; braking means to hold stationary the said brake drum to provide for low ratio forward drive; braking means to hold said annulus 'gear stationary to provide reverse rotation of said driven shaft; and clutch means to connect said rotatable member with first said shaft and serving by locking the gears of said planetary assembly to connect rst said shaft with said driven shaft to provide a direct drive.

15. In a power transmission, in combination: a planetary assembly having members including a sun gear, an annulus gear, planet gears and a rotatable planet-gear carrier; a drive shaft connected with one of the said mem- Y bers; a driven shaft connected with another of the said members; gears in said assembly being enclosed to form a fluid pump; an inlet and an outlet for said pump; valve means acting automatically to variably restrict said outlet;

7,5 spring means biasing said valve means to initial position;

and manual control means serving to make said valve means operative; wherein said valve means is automatically responsive to variations in the transmitted torque; said valve means acting to increase providing reduced resistance to the rotatiodof the gear members forming said pump; thereby providing a lower speed ratio in the drive between said shafts; said amount of ow from in the drive between said shafts.

16. In a power transmission, in combination: a planetary assembly having members including a sun gear, planet gears, an annulus gear and a planet-gear carrier; a drive means and serving, with increasing rotation of said driven shaft, to position said valve to increasingly restrict the ow from said pump; a throttle pedal; a member connected with said throttle pedal and operating on increasing opening of said throttle to position said valve to increase the ow from said pump; a cross-link connecting to variably operate said valve.

17. In propelled for the engagement of said braking means; gears in said assembly being enclosed to form a fluid pump; an inlet and an outlet for said pump; valve mechanism serving to vaiiably restrict the fluid iow from said outlet; a control 'or the operation of said valve mechanism;

the huid ow from said pump.

18. In a power transmission, more particularly in a selfpropelled vehicle, in

combination: an engine-driven shaft,

reduced drive between said second shaft and said third shaft; clutch means spring-biased to engagement and locking the gears of said assembly when engaged and a member of said assembly and operative, when said latter clutch means is engaged, to hold said third shaft and manual means serving mechanically to restrain said brake meansfrom application; said latter manual means being operable to condition said transmis a planet-carrier supporting said directly connected with the said driven shaft; a second combination: a drive gearing between said shafts; braking means serving check the rotation of a to provide modified driving between said shafts; clutching 23 serving to mechanically disengage said clutching means and to mechanically provide application of said braking means.

23. A power transmission as set forth in claim 22, including means to restrain said braking means from application by said hand brake lever when said lever is operated fo the disengagement of said clutching means.

References Cited in the file of this patent UNITED STATES PATENTS 1,256,373 Rowledge Feb. 12, 1918 1,364,392 Macho Ian. 4, 1921 1,754,385 Johnson Apr. 1, 1930 1,961,619 McLain June 5, 1934 1,975,626 Tibbetts 3 Oct. 2, 1934 2,085,897 Burrows July 6, 1937 24 Lee Nov. 8, 1938 Thoma Apr. 18, 1939 Lawrence Oct. 24, 1939 Thompson June 18, 1940 Black July 15, 1941 Barkeij Nov. 4, 1941 Dodge Mar.13, 1945 Dodge i-- Mar. 13, 1945 Kelley June 5, 1945 Thompson Nov. 4,V 1947 Backus Apr. 26, 1949 Carnegie Aug. 12, 1952 Kelbel Jan. 13, 1953 FOREIGN PATENTS Great Britain Nov. 9, 1928 

